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I have a 2001 caloi pro that i just got a new set of wheels for but as im trying to get the derallieur adjusted i noticed the chain is hitting the side of the drop out and catching on a certain part of the rotation and im wondering how to fix this, my two thoughts are that maybe the cog in the derallier is ben as it keep moving in the rotation until it hits a certain point then the chain actually gets caught and stops or that it might be the jockey pulleys in my rear derallieur as they are very very worn down ( im going to be replacing them as soon as i get a new set) which would be moving the chain over slightly during a certain point in the rotation.

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

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Where exactly is it touching on the dropout. Along the back or top, while on the smallest sprocket? Below the smallest sprocket down by the hanger? Also if it's touching on the hanger is that after you've set the high gear limit so the pulley sits below the smallest sprocket (no cable yet)?

Do you know how and have the tools to remove the lock nuts on the axle, if so if the rear spacing matched the drops outs now and if you look between the lock nuts you may have a washer between them add it to the drive side and this will move the hub in but this may also move wheel over and the correct thing would be to dish the wheel depending on how far off it is and you are not really picky or care you can adjust brake pads and leave it. It all depends on what's on that axle now if you can do this you need to look.

Where exactly is it touching on the dropout. Along the back or top, while on the smallest sprocket? Below the smallest sprocket down by the hanger? Also if it's touching on the hanger is that after you've set the high gear limit so the pulley sits below the smallest sprocket (no cable yet)?

A more detailed description will help me or others advise you.

Its hitting the side of the dropout along the bottom, i have already tried adjusting both the cable and the limits screws and i cant seem to get it not get caught up, and by smallest sprocket i am referring to the number of teeth so it would be the highest gear.

Usually when there is a touch of rub down there the chain eventually creates it's own clearance in a non-noticeable way, since at high speed your ears are hearing the wind blast.

I'm assuming that the cassette was installed properly with or without the spacer that is often supplied with the cassette.

I can't say more without a picture or good description of all the parts, but the chain wobbling back and forth must be either the pulley or the smallest cassette cog, or there's wobble in the cassette body or the lock ring's loose... ... mebbe the chain has gotten pranged or has a dislodged sideplate?

Is the smallest sprocket positioned properly with respect to the freehub splines?

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Posts: 35,431

Mentioned: 105 Post(s)

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Before going farther, shift to high and see how much room there is between the chain and dropout along the back and top where the chain is on the sprocket. If there's about 1-2mm clearance, then there's no need to respace the hub because it isn't the problem.

It's possible that the hanger is bent or twisted. If you have a yardstick try this. Shift to high, put the yardstick against the wheel vertically just behind the cassette. If all is right, the vertical section of the chain will be parallel with the edge of the yardstick. I suspect that it won't be which is why it's brushing the hanger as it leaves the jockey wheel.

Also the yardstick will give you a good frame of reference so if there is any change in the chain angle coming to the sprocket you'll see it. If the chain does "wobble" on the way up, then either the jockey wheel is damaged (or it's hub is worn out) or possibly the chain itself has a few bent or twisted plates. Either way, the good visual reference of the yardstick will help make the problem obvious.

Also if it's touching at the very back of the dropout (9 o'clock) then it's simply a case of a bent dropout, but this is usually obvious to the eye.

Before going farther, shift to high and see how much room there is between the chain and dropout along the back and top where the chain is on the sprocket. If there's about 1-2mm clearance, then there's no need to respace the hub because it isn't the problem.

It's possible that the hanger is bent or twisted. If you have a yardstick try this. Shift to high, put the yardstick against the wheel vertically just behind the cassette. If all is right, the vertical section of the chain will be parallel with the edge of the yardstick. I suspect that it won't be which is why it's brushing the hanger as it leaves the jockey wheel.

Also if it's touching at the very back of the dropout (9 o'clock) then it's simply a case of a bent dropout, but this is usually obvious to the eye.

ill take a look but i doubt that is the problem as my drop out are semi horizontal and the derallieur anger is a 1" thick piece of aluminum

Usually when there is a touch of rub down there the chain eventually creates it's own clearance in a non-noticeable way, since at high speed your ears are hearing the wind blast.

I'm assuming that the cassette was installed properly with or without the spacer that is often supplied with the cassette.

I can't say more without a picture or good description of all the parts, but the chain wobbling back and forth must be either the pulley or the smallest cassette cog, or there's wobble in the cassette body or the lock ring's loose... ... mebbe the chain has gotten pranged or has a dislodged sideplate?

Is the smallest sprocket positioned properly with respect to the freehub splines?

i swapped all the parts over myself from the old wheel and im fairly sure everything is there and in the right order but when i get back to my tools i will pull the cassette off and re-instal it to see if thats the issue.

I don't suppose any spacers carried over from the old hub, and different hubs/wheels often have enough dimensional differences to require re-adjusting the derailer, but I'd be concerned if there is any real "snagging" as you suggested, which might cause interrupted movement of the cranks?
I'm almost assuming it isn't that bad, cause then there would be a need for a saftey margin in terms of the chain clearance.

Is there any spacer at all between the back side of the cassette and the fulcrum freehub body?

Does the cassette spin straight when it's rotating with the wheel?

You and F.B. discussed the hi-limit screw, so now assuming it's as tight as will still allow shifting to the smallest cog?

Perhaps your question could also be directed to Fulcrum's customer service dept. A wheel can be built stronger and thus lighter by positioning the cassette closer to the frame, so perhaps they exploited this to the point of being incompatible with a select few framesets. I'm sure that they would want to know about this, but they may ask that you bring the bike to one of their dealers for evaluation.

Looks like the OP fixed his issue, but I ran into this when I swapped over to new wheels last night. My old aksiums actually had two spacers on it, and so I put aside what I had been told was a mavic specific spacer and just used the other one. Result was the chain rubbing on the join between the seatstay and chainstay in the 11t. Removed spacer, problem went away.